Water transport has been identified as a factor in the selection of biocompatible materials for medical applications, including ophthalmic lenses such as contact lenses. It would therefore be desirable to quantify in-vitro flux and diffusion coefficients of water, through biocompatible materials such as hydrogels.
U.S. Pat. No. 5,776,999 to Nicolson et al. discloses a method for screening materials for use as extended-wear ophthalmic lenses. The Nicolson et al. patent also discloses various methods for measuring the diffusivity of hydrogel materials.
Prior art methods for determining water transport require the preparation and use of buffered solutions. It would be desirable to provide a simpler laboratory technique that does not require the preparation and use of buffered solutions. It would also be desirable to provide a method that does not require the use of radio-labeled materials. Further, it would be desirable to provide a method that produces reliable results using readily available laboratory equipment.